1. Field of the Invention
The present invention relates to a laser diode such as a broad area type laser diode.
2. Description of the Related Art
An LD (laser diode) is not only used as a light source in an optical disk device such as a CD (Compact Disk) and a DVD (Digital Versatile Disk), but also applied to various fields such as a display, a printing product, fabricating materials, and medical care. In these application fields, high output is often desirable, and therefore, a high power laser diode is increasingly aspired.
As one method to improve output, in the case of a laser diode having a stripe-shape light emitting region, it is effective to widen a width of the light emitting region, that is, a stripe width. For example, in a laser diode for an optical disk, a typical value of the stripe width is about 2 μm to 3 μm. Meanwhile, of the laser diodes developed for high output use, a laser diode whose stripe width is widened to 50 μm to 100 μm has been introduced. The laser diode whose stripe width is widened as above is referred to as a broad area type laser diode. A specific numerical value of the stripe width, being a standard for the “broad area type” laser diode herein described has not been determined. However, in this specification, for example, the stripe width thereof shall be about 10 μm or more.